Rectification apparatus



W. W. PAGET RECTIFICATlON APPARATUS Feb. 26, 1952 Filed sept. 29, 1949 Patented Feb. 26, 1952 UNITED STATI-:s PATENT oFF-Ica nEoTIFrCATioN APPARATUS.

wm w. meer, Miehim city,

Ind., assignor to Joy Manufacturing Company, Pittsburgh, Pa.. a corporation of Pennsylvania Application september zo, 1949, serial No. 118.614 9 claims. (ci. sz- 122) 1 of the application of Samuel C. Collins, Serial Number 122,077 illed October 18, 1949, and assigned to the assigneeof this invention. The aforesaid application of Samuel C. Collins' also discloses, in Figures 2 and 3, a double-column system to which attention is invited, because the invention described and claimed herein is not limited to a single rectiilcation column such as is shown, but may be used in a double column as well. In view of the similarity of the apparatus set forth in the above identified applifrom the column in the liquid form, to withdraw the oxygen from the bottom of the liquid receiver in order to prevent the accumulation of appreciable quantities of any impurities. At the same time, however', it is usually desirable to maintain a. predetermined liquid level in the liquid receiver, because the liquid receiver usually also serves as an evaporator-condenser and it becomes desirable to have the condenser constantly submerged in liquid. 'I'hese considerations apply whether the apparatus employs a single column or a double column.

It is, accordingly, an object of this invention to provide apparatus for the separation of a gaseous mixture into its constituents in which a liquid rich in one of the constituents is withdrawn from the bottom of a receiver in which the liquid accumulates while at the same time maintaining the liquid level in the receiver at a predetermined height. More specically, it is an object of this invention to provide apparatus for the ,separation of air into its constituents -in order to produce substantially pure oxygen, in which oxygen can be withdrawn in the liquid form`from the evaporator condenser in which it accumulates in such a manner as to prevent the accumulation of impurities in the liquid while also keeping the liquid oxygen level high enough to keep the condenser submerged.

This and other objects are accomplished in apparatus which takes oxygen from the bottom of the liquid receiver and which includes a cup into which liquid oxygen overflows to maintain a desired liquid oxygen level in the liquid receiver, the liquid outlet from the cup constituting a conduit which reaches into the cup to remove liquid therefrom as it overows into the cup. The cup is so designed that the liquid volume in the cup is greater than the displacement of a positive displacement pump used to withdraw liquid from the cup.

In the drawings:

Fig. 1 is a schematic view of apparatus embodying the invention, and

Fig. 2 is an enlarged detail view, with parts broken away and in section, to s how the internal structure of the overflow device.

Except for the means whereby liquid oxygen is withdrawn from the column, theA apparatus shown in Fig. 1 is substantially the same as' Fig.

cation of Samuel C. Collins to thel apparatus of this invention, the apparatus will not be described in detail herein, except for the changes accomplished by this invention.

'I'he drawings show a single-column rectiiler u 2 having an evaporator-condenser 4 at the lower end thereof which serves'as a receiver in-which substantially pure oxygen accumulates. Invthe receiver 4 there is provided a coil y6 through which cold purified air passes and in which the puried air condenses while boiling oi the lower' boiling point constituents present in the liquid in receiver 4. I

A positivev displacement liquid oxygen pump 8 is connected to be driven by an expansion engine I0, as will be well understood by those skilled in the art. The pump 8 withdraws liquid oxygen from receiver 4 through an overflow or chamber device indicated generally at I2, the structure of which is shown in detail in Fig. 2. The overiiow or chamber device I2 is an elongated, substantially vertical device having an interior chamber I3 and, as is best seen in Fig. 1, is positioned at substantially the saine level as receiver 4. Means are provided to connect one end of the chamber with the bottom of the receiver, and other means are provided to connect the other end of. the chamber with the receiver at a point above the normal liquid level in the receiver.

The means to connect one end of the chamber with the bottom of the receiver constitutes a conduit I4 opening into the bottom of receiver 4.

Conduit I4 is connected to the lower end of the.

overflow or chamber device I2 and is provided with a liquid drain cock I5. The means to connect the other end of the device with the receiver constitutes a conduit I6 opening into the column 2 above the normal liquid level I8 in the liquid oxygen receiver 4. In order to assure a maximum eectiveness of the condenser 6, the liquid level I 8 is maintained (by means described below) at a point well above the top of coil 6, to insure that coil 6 is always submerged in oxygen-rich liquid. l

The overiiow or chamber device I2 will now be described in detail. As is best seen in Fig. 2, a substantially cylindrical member 20 isl necked down at its lower end, and near its lower end is provided with a. connection 22 which receives the end of conduit I4. At its upper end, member 20 is provided with a tting 24 having two connections other than the connection with the member 20. A connection 26 secures the con'duit Ii to the iltting 24 and serves to connect the upper end of chamber i3 with the interior oi the column at some point above the liquid level Il.: A second connection 23 is preferably provided with a sleeve or bushing 30 through which passes a conduit 22 which serves as the liquid outlet from chamber i3 and conducts liquid to the pump 3. A liquid collector cup `34 is positioned in chamber il and outlet 32 withdraws liquid trom the cup 34.

As will be well understood by those skilled in the art, the liquid outlet I2 is secured as' by soldering, brazing or other satisfactory means to the fitting 24. To this end the bushing I3 is secured directly to the tting 24 in the connection 28, and the liquid outlet-I2 is securedto the bushing 30.

Cup 34 is preferably a cylinder, open at its A upper end to provide an edge 33 over which liquid cous mixture into its constituents, a rectication column. a .receiver positioned to accumulate a liquid rich in one constituent, an elongated substantially vertical chamber device positioned at substantially the same level as the receiver. means to connect one end o! the chamber device with the bottom of the receiver to withdraw liquid from the receiver bottom. means to connect the other end of the chamber device with the receiver at a point above the normal l liquid level in the receiver, a liquid collector cup overflows into the cup, and closed at its lower end, preferably by means ci a plug 3l. The lower end of cup 34 is secured. as by soldering or brazing, to the necked-down end of member 20 at 40.

The securance of cup 34 by the necked-down end of member 20 at 40 constitutes the sole support of the cup. With this construction, it is possible to adjust the height of the edge 3l of cup 34 to the height desired for the liquid level i8. The adjustment is, of course, accomplished before the joint at 43 is soldered, or otherwise secured; when the desired adjustment has been accomplished, then the member 20 and cup 34 are securely fastened together as shown at 40.

The annular space 48 provided in cup 34 between the inside of the cup and the outside o! outlet 32 is preferably such that the liquid volume provided thereby is greater than the displacement of positive displacement pump 3. in order that the pump will not withdraw a charge which consists partially of liquid and partially of gas.

Operation In the operation ot apparatus made according to this invention, liquid is lcontinuously withdrawn from the bottom of liquid receiver 4, thus constantly withdrawing heavy impurities which It will be evident from the foregoing that thisV invention provides apparatus having the advantages that liquid may be maintained at a given desired level in a liquid receive;` and yet may be withdrawn in such a manner as to prevent the accumulation of heavy impurities in the bottom of the receiver.

While there is in this application specifically described one form which the invention may assume in practice, it will be 'understood that this form of the same is shown for purposes oi' illustration, and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

I claim: 1. In apparatus for the lsanitation oi a gesdisposed in the` chamber oi' thev chamber device with its edge at the level desired for the liquid `in the receiver, and a liquid outlet opening into said cup.

2. Apparatus `as set forth in claim l, in which the liquid outlet extends into the cup through its open end deilned by said edge to a point near the bottom. A

3. Apparatus according to vclaim 2, in which the liquid outlet is connected with a positive displacement liquld pump, thev volume of the annular space formed by the cup and the outlet being greater than thev pump displacement.

4. Apparatus according to claim 1, in which the receiver is integral with the column and is disposed at the lower end of a rectiiier section thereof.

5. In apparatus for the separation o air into its constituents, a rectier column. a receiver in the column adapted to accumulate a liquid .rich in one of the constituents, a condenser asneet the other end oi the chamber device with the receiver at a point above the normal liquid level in the receiver, a liquid collector cup disposed in the chamber of the chamber'device with its edge at the level desired for the liquid in the receiver, and a liquid outlet opening into said cup.

6. Apparatus as set forth in claim 5. in which the normal liquid levelis such as to completely submerge said associated condenser in liquid.

, '1. Apparatus according to claim 6, in which the liquid outlet is connected with a positive displacement liquid pump, the volume of the annular space formed by the cup and the outlet b eing greater than the pump displacement.

8. Apparatus according to claim 5, in which the liquid outlet is connected with a positive displacement liquid pump, the volume of the annular space formed by the cup and the outletl being greater than the pump displacement.

9. Apparatus according to claim 5. in which the sole support for said cup is provided at the lower end of said device.

WIN W. PAGET.

REFERENCES CITED The following references are ot record in the file of this patent:

UNITED STATES PATENTS 

